Sexual aversion and anxiety

I have been with my partner for over 7 years and have a 8 month old boy. I suffer from anxiety, depression and PTSD. About 4 years ago my partner cheated on me. And I found it very difficult to ‘get over it’. I find I get so worked up and triggered with any kind of intimacy, we havnt had sex for a year, and my partner thinks it cause I don’t love him. I want to want to be intimate but I’m finding it so hard. Please help